So. I'm trying to put together an approximate (hah!) timeline for Stargate prehistory. Of course, this is complicated by Stargate's own inconsistencies, and the fact that the film contradicts the episodes, which in turn contradict themselves...
Aaaanyhow. This is my rough approximation, giving preference to props (ID badges) rather than words, and the series rather than the film, and based on the idea that the series is set at about the same time that it came out:
1945: Stargate opened for the "first" time; Ernest lost.
1952: Jack born.
1965: Daniel born.
1968: Sam born.
1969: SG-1 back in time, meet Hammond, Catherine.
1973: Daniel's parents die1.
1981/82...?: Sam's mother dies2.
1985/86...?: Charlie born3.
1990/91 (during the Gulf War): Jack prisoner in Iraq for 4 months.
1995/96...?: Charlie dies.
1996: Stargate reopened, mission to Abydos (Daniel left behind).
1997: Apophis comes through Stargate, SG-1 formed, start of series.
Any thoughts gladly welcomed.
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1 NICK: I am sorry.
DANIEL: For what?
NICK: For not adopting you when your parents died.
DANIEL: You were travelling all over the world.
NICK: It wasn't your fault.
DANIEL: I was eight years old, how could it have been my fault?
2: I'm bad at assessing children's ages - she's, what, thirteen?
3: Honestly, so bad at assessing ages.
Comments
As to Charlie, he looked to be an age-mate of my eldest, who was born in March of 1985, so I've always taken 1985 to be his birthdate. You could certainly make a case for his being born in 1986 and being big for his age too, since neither of his parents are short. I don't think that canon offers anything that would tie the birthdate down firmly.
By now you've probably made your decisions as to what the time line is, since I was away for the weekend and didn't see this until now. But for what it's worth, those are my two cents.
When we hear the offscreen shot in the flashback to Charlie's death the leaves are green and well established. When General West's men come to take Jack to Cheyenne Mountain for the suicide mission it is also green and leafy. So unless we think that Jack was actually sitting on that bed holding the gun and threatening suicide for about a full year, General West's men came and got him in the same season, or at least within a month or so of the time of Charlie's death. I can't imagine that Sara would put up with that for a whole year, so I'd imagine that Charlie died in 1996, when the movie takes place.